Restless leg syndrome (RLS) is a neurosensorimotor disorder with parestethesias, sleep disturbances and, in most cases, periodic limb movements of sleep (PLMS).
Pramipexole is a dopamine-D.sub.3 /D.sub.2 agonist the synthesis of which is described in European Patent 186 087 and its counterpart, U.S. Pat. No. 4,886,812. It is known primarily for the treatment of schizophrenia and Parkinson's disease. It is known from German patent application DE 38 43 227 that pramipexole lowers the plasma level of prolactin. Also, this European patent application discloses the use of pramipexole in the treatment of drug dependency. Further, it is known from German patent application DE 39 33 738 that pramipexole can be used to decrease abnormal high levels of thyroid stimulating hormone (TSH). U.S. Pat. No. 5,112,842 discloses the transdermal administration of the compounds and transdermal systems containing these active compounds. The WO patent application PCT/EP 93/03389 describes pramipexole as an antidepressant agent, while the PCT application PCT/US95/15618 discloses the neuroprotective effects of pramipexole.
Surprisingly and unexpectedly, it has been found that pramipexole and the pharmacologically acceptable salts thereof can be used in the treatment of restless leg syndrome.